1. Field of the Invention
The present invention relates to disposable napkin-knickers having a generally rectangular shape and of the type comprising a flexible and impermeable support sheet with an absorbent wad disposed on the support sheet and a flexible and permeable upper sheet covering the absorbent wad and with the upper sheet being fixed in at least a part of its periphery to the support sheet.
2. Description of the Prior Art
Different types of napkin-knickers are known from the prior art among which two essential categories must be specifically mentioned.
In a first category, there are napkin-knickers which are said to be anatomically cut out and comprise, in the conventional manner, an absorbent wad or pad inserted between an impermeable support sheet and a permeable upper sheet, these two sheets being interconnected in the region of their periphery.
In order to moderate the inconvenience felt by the users of the napkin and thus improve their comfort, the coverings and the wad of such napkins are cut out in the crotch so as to reduce the width thereof and thus afford an anatomical shape.
Further, in order to ensure the fluid tightness of these napkins when they are worn by a user, they are provided with an elastic system for creating a barrier for leakages of liquid excrement, this elastic system being simple or multiple, i.e. having respectively two or more than two elastic bands.
Two cut-out shapes have been adopted. On one hand, a cut-out in the shape of an hour-glass associated with an elastic fluid tight system placed at more than 19 mm from the edge of the wad and, on the other hand, an H-shaped cut-out associated with an elastic sealing system placed at less than 19 mm from the edge of the wad.
However, while napkin-knickers belonging to this category substantially improve the comfort to the user, it nonetheless remains that their manufacture, which employs particular cut-outs, has been consequently found to be relatively complex and, therefore, requires costly machines which have the further drawback of only being able to manufacture a given cut-out.
U.S. Pat. No. 4,430,086 discloses a contoured diaper or napkin-knicker, which employs two separate elastic members, each of the same width and material, even though one of the elastic members in an embodiment may be initially tensioned to a greater degree than the other elastic member.
In a second category, the drawings resulting from the construction of special shapes of napkins are avoided in that there are provided napkins having a generally rectangular shape on which there is provided an elastic sealing system comprising one or more elastic bands which are parallel to each other and generally disposed longitudinally along the edge of the napkin or in the region of the absorbent wad, on or under the latter.
Further, in order to perfect the shaping of such napkins to the anatomical shape of the user and, in particular, in the region of the crotch of the user, the width of the napkin is reduced in this region by a folding of the lateral edge portions of the napkin, which at the same time provides a retention pocket in the crotch.
However, the last-mentioned arrangements do not satisfactorily solve the problem posed by the discomfort felt by the user.